High-frequency discharge tube apparatus



ZAQKQQ ipkby 1%) D. ZAAYER ET AL HIGH-FREQUENCY DISCHARGE TUBE APPARATUS 2 Sheets-Sheet 1 Filed May 2, 1946 DAVID 21mm 21mm) GERADUSDORGELO INVENTORS.

v ATTORJEY FMS. 114, HQEQ ZAAYERV r AL 2 49?}8U9 HIGH-FREQUENCY DISCHARGE TUBE APPARATUS Filed May 2, 1946 2 Sheets-Sheet 2 flAVZD ZAA YER.

EDUAED GERADUSDOEGELO IN VEN TORS.

AT T 013N51 Patented Feb. 14, 1950 HIGH-FREQUENCY DISCHARGE TUBE APPARATUS David Zaaycr and Eduard Gerardus Dorgelo, Eindhoven, Netherlands, assignors, by mcsne assignments, to Hartford National Bank and Trust Company, Hartford, Conn, as trustee Application May 2, 1946, Serial No. 666,564 In the Netherlands April 17, 1942 Section 1, Public Law 690, August 8, 1946 Patentexpires April 1'7, 1962 9. Claims. 1

The. invention relates to a circuit-arrangement comprising two discharge tubes whose walls consist of insulating material and each of which comprises an electrode system, inter alia at least an anode, while the. output circuit is formed by an oscillatory circuit consisting of two parallel conductors.

If such a circuit-arrangement is utilized for the generation or amplification of oscillations of high andultra high-frequency there arise drawbacks. due. to the. connections through the intermediary of which: the anodes are connected to the conductors located outside the tube, which conductors carry a current of frequency. Thus, the high-frequency resistance of these connections causes extra losses which give rise, moreover, to an undesired. heating of the seals. According to the invention, in order to relieve these seals and to obtain a constructionally simple mode of realization of the circuit-arrangement concerned, the conductors of the oscillatory circuit are given the form of tubes while each conductor encloses the wall of a tube over at least a great proportion of'the entire length of the anode and is capacitatively coupled with the anode in question, With the aid of the circuit..- arrangement accordingto the invention, wherein consequently for high frequencies a direct connectlon between. the anodes and the conductors of the oscillatory circuit which are located 'out-' side the tube and which carry current of high frequency, and the losses attended therewith are avoided, it is possible to utilize small transmitting tubes for the production or amplification of a' comparatively large power;

A detailed explanation follows with reference to the accompanying drawings whereinf.

vFig; 1 is a schematic circuit diagram illus-E trating a conventional push-pull oscillatory arrangement.

Fig. 2 shows a longitudinal section through apreferred embodiment of an oscillatory device constructed in accordance with the invention.

' Fig. 3 is a transverse section taken on linev output circuits land 8 are each formed. by an.

oscillatory circuit which consists of two parallel conductors. 9, and IE3 respectively, the conductors 9 and i0 being connected. to the grids 5 and the anodes 5 respectively of the tubes 6 and 2. For the suppression of reaction between the circuits l and 8 there are provided neutralizing condensers it each of which connects the conductor surrounding the anode 6 of a tube capacitatively with the grid 5 of the other tube. To the anodes of the tubes is applied a voltage which is positive with respect to. the cathodeswhereas a voltage which is. negative with respect to the cathodes is applied to the grids. For the sake of simplicity the sources of supply are not shown in the figures.

In the constructional mode of realization of the circuit arrangement shown in Fig. 1, which is utilized in accordance with the invention and which is represented in Figs. 2 and 3 in 1ongitudinal and in transverse section, the conductors IQ. of the oscillatory circuit 8 have the form of tubes while each conductor ii] encloses the envelope 3. of one of the tubes l and 2 over substantially the entire length of the cylindrical anode 6 so that the conductor, is capacitatively coupled with the latter. Owing to this method of. connecting the anode with the parts outside the tube which carry current of high frequency, the usual inconveniences of the sealing-in operation and the, losses attended therewith are avoided. 'The anode direct-current voltage is supplied, via a choke coil l2 and. a seal it in the wall of the tube, to the anode 6 of each tube. Since-the conductor connecting the anode to the choke coil located outside. the tube is only tray-- ersed by'direct current, the seal is as a rule not subjected to a heavy load. Since the wall 3 of the. tube acts as the dielectrics of the condensers formed by the anodes 6 and the conductors ill, the wall of the tube is preferably made of quartz since quartz practically causes no losses even at. high temperatures.

Furthermore, in the mode of realization accordin to the invention, the conductors 9 of the inputv circuit 7, which consists of two parallel conductors, likewise have the form of tubes while having. se'curedto themtwo plug bushes it which.

are connected toyone another by means of conductive strips 86, as is shown in Fla. 3 whichrepresent a section on the line III-III in Fig.

2. The connection of the conductors 9 with the grids of the tubes I and 2 is established by means of a conductive ring I! which fits around the lower end of the tube and which is conductively connected to the output leads l8 of the grid which are located within the tube. The cathodes of the tubes l and 2, which cathodes are each con nected to two plug pins I9 which fit into the plug bushes I5, are connected in parallel by means of the conductive strips l6. To the mid-points 20 of the strips l6 are connected conductors 21 through the intermediary of which the heating current is supplied to the cathodes.

In order to avoid undesired coupling between the conductors .l and H3, a screening member 22 is preferably provided between those ends of these conductors which are turned towards one another.

Figs. 4 and 5 represent a lateral elevation and a plan view respectively of the device according to Figs. 2 and 3, wherein neutralizing condensers I l are visible. For the sake of clearness the plate 22 is not shown in Fig. 5. The electrodes of the neutralizing condensers are formed by the conductors In which surround the anodes 6 and by plates 23 which are arranged opposite the said conductors and whose distance with respect to the conductors ill and therefore the value of the capacity can be exactly adjusted by means of a micrometer screw 24. By means of conductors 25 the electrodes 23 of the neutralizing condensers are crosswise connected to the grids 5 of the tubes I and 2. Owing to the arrangement of the neutralizing condensers in the manner shown in Figs. 4 and 5 we obtain the advantage that when any one of the tubes 1 and 2 has to be replaced by a fresh tube the position of the electrodes 23 needs only a slight correction for compensating the tube capacity differences. If, however, an anode were utilized directly as one of the electrodes of a neutralizing condenser, the latter would have to be submitted to great corrections in the case of replacement of one of the tubes by another since in the arrangement and in the dimensions of the tube there occur far greater variations than is admitted by the adjustment of the neutralizing condenser. In the construction shown, however, each neutralizing condenser H is connected to the anode via the capacity between the tubular conductor [0 and the appurtenant anode, this capacity having so high a value that a variation in the dimensions and in the arrangement of the tube has substantially no influence on the value thereof and therefore on the adjustment of the neutralizing condenser.

' We claim:

' 1. High-frequency push-pull circuit apparatus comprising two discharge tubes each including an electrode system having at least a cathode and an elongated anode and an insulating enevelope surrounding said electrode system, and a parallel-resonant transmission line output circuit including two tubular conductors disposed in parallel relation, each of said conductors enclosing the envelope of one of said tubes over a major portion of the entire length of said anode whereby each of said conductors is capacitatively connected to the corresponding anode.

2. High-frequency push-pull circuit apparatus comprising two discharge tubes each including an electrode system having at least a cathode and a cylindrical anode and an insulating envelope" surrounding said electrode system, and a parallel-resonant transmission line output circuit including two tubular conductors disposed in parallel relation, each of said conductors enclosing the envelope of one of said tubes over a major portion of the entire length of said cylindrical anode whereby each of said conductors is capacitatively coupled to the corresponding anode.

3. High-frequency push-pull circuit apparatus comprising two discharge tubes each including an electrode system having at least a cathode and a cylindrical anode, a cylindrical insulating envelope surrounding said electrode system in concentric relation with said anode, and an anode terminal externally disposed on one end of said envelope, a parallel-resonant transmission line output circuit including two tubular conductors positioned in parallel relation, each of said conductors enclosing the envelope of one of said tubes over a major portion of the entire length of said cylindrical anode whereby each of said conductors is capacitatively coupled to the corresponding anode, said anode terminal being contained within said tubular conductor, and con-' necting means within each of said conductors for applying a potential to said anode terminal.

4. High-frequency push-pull circuit apparatus comprising two discharge tubes each including an electrode system having at least a cathode and a cylindrical anode, an insulating envelope surrounding said electrode system in concentric relation with said anode, and an anode terminal projecting axially from a seal in one end of said envelope, a parallelresonant transmission line output circuit including two tubular conductors positioned in parallel relation, each of said conductors enclosing the envelope of one of said tubes over a major portion of the entire length of said cylindrical anode whereby each of said conductors is capacitatively coupled to the corresponding anode, said anode terminal being contained within said tubular conductor and connecting means including a radio-frequency choke coil disposed within each of said conductors for applying a potential to said anode terminal.

5. High-frequency push-pull circuit apparatus comprising two discharge tubes each including an electrode system having at least a cathode and a cylindrical anode and a cylindrical quartz envelope surrounding said electrode system, said envelope being concentrically disposed about said anode, and a parallel-resonant transmission line output circuit including two tubular conductorspositioned in parallel relation, each of said conductors enclosing the envelope of one of said tubes over substantially the entire length of said cylindrical anode whereby each of said conductors is capacitatively coupled to the corresponding anode, said quartz envelope acting as a dielectric between the anodes and the respectiv surrounding conductors.

6. High-frequency push-pull circuit apparatus comprising two discharge tubes each including an electrode system having at least a cathode, a grid and an elongated anode and an insulating envelope surrounding said electrode system, a

parallel-resonant transmission line output circuit including two tubular conductors positioned in parallel relation, each of said conductors enclos-' ing the envelope of one of said tubes over a major portion of the entire length of said anode whereby each of said conductors is capacitatively coupled to the corresponding anode, and a neutralizing circuit connecting the anodes crosswise to the grids of said two tubes, said neutralizing cir-- cuit including two adjustable electrodes, each electrode being connected to a respective grid and a grid and an elongated anode and an insulatin envelope surrounding said electrode system, a

parallel -resonant transmission line output circuit including two tubular conductors positioned in parallel relation, each of said conductors enclosing the envelope of one of said tubes over a major portion of the entire length of said anode whereby each of said conductors is capacitatively coupled to the corresponding anode, and a neutralizing circuit connecting the anodes crosswise to the grids of said two tubes, said neutralizing ,circuit including two arcuate plates each connected to a respective grid and positioned in parallel relation to one of said conductors to form therewith a neutralizing condenser, and means coupled to said plates to simultaneously adjust the spacing of said plates relative to said conductors. 8. High-frequency push-pull circuit apparatus comprising two discharge tubes each including an electrode system having at least a cathode, a grid and a cylindrical anode, a cylindrical insulating envelope surrounding said electrode system in concentric relation with said anode,

and an annular grid terminal fitted about said cylindrical envelope at one end thereof, a parallel-resonant transmission line output circuit envelope oione of said tubes over majorportion of the entirelength of said cylindrical anode whereby each? of said conductors in-said first pair is capacitatively coupled to the corresponding anode, --Eand a-p'arallel-resonant transmission line input circuit including a second pair of tubular conductors, the annular g-ri'd terminals of said'tubes'beirig received withinthe ends of said conductorsin said second pair whereby said conductorsareconnected to the grids of'said tubes and also actz' aj's holders therefor. l,

9. An oscillatory" circuit in accordance with claim 8 furthergincluding a screening member interposed between adjacent ends of said first pair and said second pair of tubular conductors.

D. ZAAYER. EDUARDY-L GERARDUS DORGELO.

REFERENCES CITED The following references are of record in the file of this patent;

UNITED STATES PATENTS 

